Submission #939670

#	Time	Username	Problem	Language	Result	Execution time	Memory
939670		haxorman	Dancing Elephants (IOI11_elephants)	C++14	97 / 100	9016 ms	23228 KiB

elephants

#include "elephants.h"
#include <bits/stdc++.h>
using namespace std;

const int mxN = 150007;
const int SZ = 388;

int n, l, step, pos[mxN], bkt[mxN], to[mxN], cnt[mxN], sz[SZ];
set<pair<int,int>> st;
pair<int,int> arr[SZ][3*SZ];

void fix(int b) {
    for (int i = sz[b]-1; i >= 0; --i) {
        int val = arr[b][i].first + l;

        if (val >= arr[b][sz[b]-1].first) {
            to[arr[b][i].second] = val;
            cnt[arr[b][i].second] = 1;
        }
        else {
            auto it = upper_bound(arr[b],arr[b]+sz[b],make_pair(val,INT_MAX));

            to[arr[b][i].second] = to[it->second];
            cnt[arr[b][i].second] = cnt[it->second] + 1;
        }
    }
}

void construct() {
    for (int i = 0; i < SZ; ++i) {
        sz[i] = 0;
    }
    
    vector<pair<int,int>> vec(n);
    for (int i = 0; i < n; ++i) {
        vec[i] = {pos[i], i};
    }
    sort(vec.begin(), vec.end());

    for (int i = 0; i < n; ++i) {
        bkt[vec[i].second] = i/SZ;
        arr[i/SZ][sz[i/SZ]++] = vec[i];
    }

    for (int b = 0; b < SZ; ++b) {
        fix(b);
    }
}

void init(int N, int L, int X[]) {
    n = N, l = L;
    
    for (int i = 0; i < n; ++i) {
        pos[i] = X[i];
        st.insert({pos[i], i});
    }

    construct();
}

int update(int i, int y) {
    for (int j = 0; j < sz[bkt[i]]; ++j) {
        if (arr[bkt[i]][j].second == i) {
            arr[bkt[i]][j] = {INT_MAX,INT_MAX};
            sort(arr[bkt[i]], arr[bkt[i]]+sz[bkt[i]]);
            sz[bkt[i]]--;
            break;
        }
    }
    fix(bkt[i]);
    
    for (int b = 0; b < SZ; ++b) {
        if (b == SZ-1 || (sz[b] && arr[b][sz[b]-1].first > y)) {
            bkt[i] = b;
            arr[b][sz[b]++] = {pos[i] = y, i};
            sort(arr[b], arr[b]+sz[b]);
            
            fix(b);
            break;
        }
    }
    
    int ans = 0, cur = -1;
    for (int b = 0; b < SZ; ++b) {
        if (sz[b] && arr[b][sz[b]-1].first > cur) {
            auto it = upper_bound(arr[b],arr[b]+sz[b],make_pair(cur,INT_MAX));

            ans += cnt[it->second];
            cur = to[it->second];
        }
    }

    step++;
    if (step == SZ) {
        construct();
        step = 0;
    }
    return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 24 / 24
• Subtask 4: 47 / 47
• Subtask 5: 0 / 3